New records of spirurid nematodes (Nematoda, Spirurida, Guyanemidae, Philometridae & Cystidicolidae) from marine fishes off New Caledonia, with redescriptions of two species and erection of Ichthyofilaroides n. gen. František Moravec, Jean-Lou Justine To cite this version: František Moravec, Jean-Lou Justine. New records of spirurid nematodes (Nematoda, Spirurida, Guyanemidae, Philometridae & Cystidicolidae) from marine fishes off New Caledonia, with redescrip- tions of two species and erection of Ichthyofilaroides n. gen.. Parasite, EDP Sciences, 2020, 27, pp.5. 10.1051/parasite/2020003. hal-02468917 HAL Id: hal-02468917 https://hal.sorbonne-universite.fr/hal-02468917 Submitted on 6 Feb 2020 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Parasite 27, 5 (2020) Ó F. Moravec & J.-L. Justine, published by EDP Sciences, 2020 https://doi.org/10.1051/parasite/2020003 urn:lsid:zoobank.org:pub:89A05EAA-F938-45F1-876E-AAC706BFA112 Available online at: www.parasite-journal.org RESEARCH ARTICLE OPEN ACCESS New records of spirurid nematodes (Nematoda, Spirurida, Guyanemidae, Philometridae & Cystidicolidae) from marine fishes off New Caledonia, with redescriptions of two species and erection of Ichthyofilaroides n. gen. František Moravec1,* and Jean-Lou Justine2 1 Institute of Parasitology, Biology Centre of the Czech Academy of Sciences, Branišovská 31, 370 05 České Budějovice, Czech Republic 2 Institut Systématique Évolution Biodiversité (ISYEB), Muséum National d’Histoire Naturelle, CNRS, Sorbonne Université, EPHE, Université des Antilles, Rue Cuvier, CP 51, 75005 Paris, France Received 2 December 2019, Accepted 13 January 2020, Published online 27 January 2020 Abstract – Recent examinations of spirurid nematodes (Spirurida) from deep-sea or coral reef marine fishes off New Caledonia, collected in the years 2006–2009, revealed the presence of the following five species: Ichthyofilaroides novaecaledoniensis (Moravec et Justine, 2009) n. gen., n. comb. (transferred from Ichthyofilaria Yamaguti, 1935) (females) (Guyanemidae) from the deep-sea fish Hoplichthys citrinus (Hoplichthyidae, Scorpaeniformes), Philometra sp. (male fourth-stage larva and mature female) (Philometridae) from Epinephelus maculatus (Serranidae, Perciformes), Ascarophis (Dentiascarophis) adioryx Machida, 1981 (female) (Cystidicolidae) from Sargocentron spiniferum (Holocentridae, Beryciformes), Ascarophis (Ascarophis) nasonis Machida, 1981 (males and females) from Naso lituratus and N. unicornis (Acanthuridae, Perciformes), and Ascarophisnema tridentatum Moravec et Justine, 2010 (female) from Gymnocranius grandoculis (Lethrinidae, Perciformes). Two species, I. novaecaledoniensis and A. nasonis, are redescribed based on light microscopical (LM) and scanning electron microscopical (SEM) examina- tions, the latter used in these species for the first time. Morphological data on the specimen of A. tridentatum from the new host species are provided. Philometra sp. (from E. maculatus) most probably represents a new gonad-infecting species of this genus. The newly established genus Ichthyofilaroides n. gen. is characterized mainly by the presence of a small buccal capsule and by the number and distribution of cephalic papillae in the female; it is the sixth genus in the Guyanemidae. Key words: Spirurida, Acanthuridae, Holocentridae, Hoplichthyidae, Serranidae, South Pacific. Re´sume´ – Nouvelles mentions de nématodes spirurides (Nematoda, Spirurida, Guyanemidae, Philometridae & Cystidicolidae) de poissons marins de la Nouvelle-Calédonie, avec redescriptions de deux espèces et érection d’Ichthyofilaroides n. gen. L’étude récente de nématodes Spirurida de poissons marins de mer profonde ou des récifs coralliens au large de la Nouvelle-Calédonie, collectés dans les années 2006-2009, a révélé la présence des cinq espèces suivantes : Ichthyofilaroides novaecaledoniensis (Moravec et Justine, 2009) n. gen., n. comb. (transféré depuis Ichthyofilaria Yamaguti, 1935) (femelles) (Guyanemidae) du poisson de profondeur Hoplichthys citrinus (Hoplichthyidae, Scorpaeniformes), Philometra sp. (larve mâle de quatrième stade et femelle mûre) (Philometridae) d’Epinephelus maculatus (Serranidae, Perciformes), Ascarophis (Dentiascarophis) adioryx Machida, 1981 (femelle) (Cystidicolidae) de Sargocentron spiniferum (Holocentridae, Beryciformes), Ascarophis (Ascarophis) nasonis Machida, 1981 (mâles et femelles) de Naso lituratus et N. unicornis (Acanthuridae, Perciformes), et Ascarophisnema tridentatum Moravec et Justine, 2010 (femelle) de Gymnocranius grandoculis (Lethrinidae, Perciformes). Deux espèces, I. novaecaledoniensis et A. nasonis, sont redécrites sur la base de la microscopie optique et de la microscopie électronique à balayage, cette dernière étant utilisée pour la première fois chez ces espèces. Des données morphologiques sur le spécimen d’A. tridentatum de la nouvelle espèce hôte sont fournies. Philometra sp. (d’E. maculatus) représente très probablement une nouvelle espèce infectant les gonades de ce genre. Le genre nouvellement établi Ichthyofilaroides n. gen. se caractérise principalement par la présence d’une petite capsule buccale et par le nombre et la répartition des papilles céphaliques chez la femelle. C’est le sixième genre des Guyanemidae. *Corresponding author: [email protected] This is an Open Access article distributed under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. 2 F. Moravec and J.-L. Justine: Parasite 2020, 27,5 Introduction musculature, surface of visceral organs and body cavity of mar- ine fishes. Nematodes of the conventional order Spirurida Chitwood, Type species: I. novaecaledoniensis (Moravec et Justine, 1933 [3, 8, 12] from marine fishes off New Caledonia have pre- 2009) n. comb. viously been dealt with in several papers [15–17, 28–43], mostly reporting various species of philometrids, camallanids Ichthyofilaroides novaecaledoniensis and cystidicolids, less often gnathostomatids or a guyanemid. Nevertheless, taking into account the wealth of marine fish (Moravec et Justine, 2009) n. comb. Figures 1, 2 species in New Caledonian waters, it is expected that the nema- Host: Lemon ghost flathead Hoplichthys citrinus Gilbert tode fauna of marine fishes, including spirurids, still remains (Hoplichthyidae, Scorpaeniformes). poorly known. Site of infection: Unknown with precision, parasites Recent examinations of spirurid nematodes collected by obtained from wash of organs in abdominal cavity of frozen- J.-L. Justine and his students in marine fishes from off New thawed fish. Caledonia in the years 2006–2009 revealed the presence of five Locality: Off New Caledonia, deep-sea cruise TERRASSE species of these parasites, two of which were previously insuf- 0 0 [54]. JNC2776, station CP3048, 23°44 S, 168°16 E, 19 October ficiently well described and two are newly recorded in New 2008, depth 380–400 m; JNC2791, JNC2795, station CP3089, Caledonian waters. Results of this study are presented herein. 0 0 22°17 S, 167°12 E, 25 October 2008, depth 390–410 m. Prevalence, intensity and details of fish: 14% (3 fish infected/22 fish examined); 1–2 nematodes. The infected fish Materials and methods (JNC2776, JNC2791 and JNC2795) were 210–215 mm in total length, 36–38 g in weight. Fish were caught off New Caledonia by various means; fish Deposition of voucher specimens: Muséum National from the deep-sea campaign were frozen-thawed. We generally d’Histoire Naturelle, Paris, France (1 specimen and 2 body used the “wash” method [18]. The nematodes for morphologi- fragments in 70% ethanol, MNHN JNC2776, JNC2791 and cal studies were fixed in hot 4% formalin or 70% ethanol. For JNC2795). light microscopical examination (LM), they were cleared with glycerine. Drawings were made with the aid of a ZEISS micro- Description scope drawing attachment. Specimens used for scanning electron microscopical (SEM) examination were postfixed in Female (four gravid specimens): Body filiform, whitish, 1% osmium tetroxide (in phosphate buffer), dehydrated through 20.21–26.33 mm long, maximum width near middle of body a graded acetone series, critical-point-dried and sputter-coated 245–354, tapering at both ends. Cuticle smooth. Anterior end with gold; they were examined using a JEOL JSM-7401F bluntly rounded (Figs. 1A–1C and 2A). Cephalic papillae scanning electron microscope at an accelerating voltage of small, indistinct in lateral view. Oral aperture small, circular, 4 kV (GB low mode). All measurements are in micrometres surrounded by cephalic papillae arranged in two circles: four unless otherwise indicated. The fish nomenclature adopted larger submedian papillae of outer circle and four smaller sub- follows FishBase [11]. median papillae of inner circle; pair of small lateral amphids present (Figs. 1F and 2A–2C). Small buccal capsule 6 long and 7–9 wide present (Fig. 1D). Muscular oesophagus narrow, Results almost cylindrical, 261–339 long and 24–39 wide at